DE 10 331 358 A1 shows a setup device for the manufacture of fuselage shells for an aircraft, which fuselage shells comprise fiber composite materials. In order to increase the strength of the fuselage shell the latter comprises stringers that extend so as to be spaced apart from each other. On a plane base carrier a grid of several supporting walls of different lengths are attached in such a manner that the ends of said supporting walls form a semicircle, wherein said supporting walls are arranged at angles to the base carrier, which angles are predetermined by the radius of the semicircle. At the distal ends of the supporting walls, which distal ends form the semicircle, modular profiles are attached that cover the interspaces between the supporting walls, with the outer surface of said profiles corresponding to the negative shape of the inner contour of the integral structural component to be manufactured. The grid of the supporting walls and the partition of the modular profiles are designed in such a manner that the gap of the modular profiles is in each case arranged underneath the position of a stringer. After preparation of the complete structure of the component and of the auxiliary materials, a suitable laminating-bonding device is placed in a precisely fitting manner above this assembly carrier, and the circumferential sealing compound that has previously been applied to the vacuum film or foil is compressed in such a manner that a vacuum-tight seal arises between the vacuum skin and the laminating-bonding device. Subsequently, the layer structure is evacuated on the side of the laminating-bonding device.
The fuselage shell comprising the stringers is made with the previously described setup device in that at first the outer surfaces of the modular profiles are covered by means of a loosely resting film or foil. Subsequently, the hollow space formed by the interspaces between the profiles is evacuated so that the film or foil is aspirated and is drawn into the profile grooves of the indentations in a form-fitting manner. After this, auxiliary materials can be placed onto the deep-drawn vacuum film or foil. Thereafter, stringer profiles embedded in supporting elements are placed into the profile grooves covered by the vacuum film or foil.
Positioning the stringer takes place by way of the matching geometries of the shaped parts that form the depression and the supporting elements. Depending on the manufacturing process, all the skin layers comprising fiber composite materials are placed, individually or as a packet, onto the outer surfaces of the modular profiles of the assembly carrier, which outer surfaces are covered by the vacuum film or foil, and onto the stringer profiles. Subsequently an optimized quantity of a sealing compound is applied to the vacuum film or foil. By precisely-fitting moving together the structure prepared in this manner onto the setup device with the laminating-bonding device the circumferential sealing compound is compressed in such a manner that a vacuum-tight seal between said vacuum film or foil and the laminating-bonding device arises. In order to accomplish the transfer of the complete construct from the setup device to the laminating-bonding device, the side of an additional setup device is vented and subsequently a vacuum is drawn on the side of the laminating-bonding device. As a result of this the entire construct is pressed at atmospheric pressure against the laminating-bonding device, and, finally, both devices are moved apart and the laminating-bonding device is rotated in order to then deliver the shell component manufactured in this manner to a curing process.
However, in the case of substantial opening angles of large fuselage shells this manufacturing method is associated with problems. Because of the substantial opening angles, the auxiliary materials and the stringer base areas during movement into the laminating-bonding device can rub against the outer positions of the sticking wet skin located therein, and consequently the form surface needs to be designed so as to be slightly smaller. To prevent the stringer and the auxiliary materials from bridging the required gap in an uncontrolled manner during transfer within the laminating-bonding device, and to prevent the former with the turned up vacuum film or foil from being simply taken along, a defined approach movement of the stringers and of the auxiliary materials is necessary.
Depending on the design of the stiffening elements in longitudinal direction (stringers), which can, for example, be designed as Ω-stringers or T-stringers, an undercut occurs that impedes the setup device and the laminating-bonding device from moving apart from each other. While the cavities for receiving the stringers on the setup device can be cut free in such a manner that moving apart is ensured, this results, however, in fixation of the auxiliary materials as a further problem in the case of substantial opening angles. Said auxiliary materials are usually placed onto, and affixed to, the free region between the stringer cavities If the stringer cavity is then substantially cut free, there remains hardly any room for exact positioning of the auxiliary materials.
While all these problems relating to manufacturing techniques occur in the manufacture of fuselage shells by means of the ARV and the laminating-bonding device, they analogously also exist during the manufacture of closed fuselage barrels. Since the above-described setup device/laminating-bonding device, which devices can be moved apart, cannot be used in the manufacture of closed fuselage barrels, special setup devices exist for this purpose in the state of the art.
In EP 2 062 814 A1 such a special setup device for the manufacture of closed fuselage barrels is disclosed. The special setup device essentially comprises a star-shaped base structure whose ends in each case are designed as form channels to accommodate stringers, thus forming part of the supporting surface for the setup process. The remaining part of the supporting surface is formed by radially-adjustable shaped pieces in which several form channels, situated side by side, are designed for receiving stringers. These radially movable shaped pieces are in each case arranged between two adjacent rigid end pieces of the base structure; they are moved by means of an air cushion, arranged between the base structure and the inside of the shaped pieces, opposite the form channels, in each case between a retracted position and an extended position. In the extended position of the shaped pieces, in cooperation with the rigid end pieces, the closed supporting surface for the positive setup of the fuselage barrel to be manufactured is formed.
For manufacturing the fuselage barrel, the supporting surface, which comprises stringers and any further extension elements, is subsequently wrapped in a tape comprising composite material. Subsequently an outer membrane is placed onto the wrapping layer, and the fuselage barrel is cured in the conventional manner with the use of pressure and temperature. Thus in this method-related step the setup device also carries out the function of a laminating-bonding device.
After curing, the device is to be removed from the fuselage barrel, for which purpose the radially-adjustable shaped pieces are transferred to their retracted position after ventilation of the air cushion. However, pulling the device from the fuselage barrel is impeded by the rigid end pieces of the base structure.
Other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.